net: filter: BPF testsuite

The testsuite covers classic and internal BPF instructions.
It is particularly useful for JIT compiler developers.
Adds to "net" selftest target.

The testsuite can be used as a set of micro-benchmarks.
It measures execution time of each BPF program in nsec.

This patch adds core framework.

Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Alexei Starovoitov 2014-05-08 14:10:52 -07:00 committed by David S. Miller
parent 9739eef13c
commit 64a8946b44
4 changed files with 343 additions and 1 deletions

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@ -1620,6 +1620,19 @@ config TEST_USER_COPY
If unsure, say N.
config TEST_BPF
tristate "Test BPF filter functionality"
default n
depends on m
help
This builds the "test_bpf" module that runs various test vectors
against the BPF interpreter or BPF JIT compiler depending on the
current setting. This is in particular useful for BPF JIT compiler
development, but also to run regression tests against changes in
the interpreter code.
If unsure, say N.
source "samples/Kconfig"
source "lib/Kconfig.kgdb"

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@ -33,6 +33,7 @@ obj-y += kstrtox.o
obj-$(CONFIG_TEST_KSTRTOX) += test-kstrtox.o
obj-$(CONFIG_TEST_MODULE) += test_module.o
obj-$(CONFIG_TEST_USER_COPY) += test_user_copy.o
obj-$(CONFIG_TEST_BPF) += test_bpf.o
ifeq ($(CONFIG_DEBUG_KOBJECT),y)
CFLAGS_kobject.o += -DDEBUG

322
lib/test_bpf.c Normal file
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@ -0,0 +1,322 @@
/*
* Testsuite for BPF interpreter and BPF JIT compiler
*
* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of version 2 of the GNU General Public
* License as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/init.h>
#include <linux/module.h>
#include <linux/filter.h>
#include <linux/skbuff.h>
#include <linux/netdevice.h>
#include <linux/if_vlan.h>
#define MAX_SUBTESTS 3
#define MAX_DATA 128
#define MAX_INSNS 512
#define MAX_K 0xffffFFFF
/* define few constants used to init test 'skb' */
#define SKB_TYPE 3
#define SKB_MARK 0x1234aaaa
#define SKB_HASH 0x1234aaab
#define SKB_QUEUE_MAP 123
#define SKB_VLAN_TCI 0xffff
#define SKB_DEV_IFINDEX 577
#define SKB_DEV_TYPE 588
/* redefine REGs to make tests less verbose */
#define R0 BPF_REG_0
#define R1 BPF_REG_1
#define R2 BPF_REG_2
#define R3 BPF_REG_3
#define R4 BPF_REG_4
#define R5 BPF_REG_5
#define R6 BPF_REG_6
#define R7 BPF_REG_7
#define R8 BPF_REG_8
#define R9 BPF_REG_9
#define R10 BPF_REG_10
struct bpf_test {
const char *descr;
union {
struct sock_filter insns[MAX_INSNS];
struct sock_filter_int insns_int[MAX_INSNS];
};
enum {
NO_DATA,
EXPECTED_FAIL,
SKB,
SKB_INT
} data_type;
__u8 data[MAX_DATA];
struct {
int data_size;
__u32 result;
} test[MAX_SUBTESTS];
};
static struct bpf_test tests[] = {
{
"TAX",
.insns = {
BPF_STMT(BPF_LD | BPF_IMM, 1),
BPF_STMT(BPF_MISC | BPF_TAX, 0),
BPF_STMT(BPF_LD | BPF_IMM, 2),
BPF_STMT(BPF_ALU | BPF_ADD | BPF_X, 0),
BPF_STMT(BPF_ALU | BPF_NEG, 0), /* A == -3 */
BPF_STMT(BPF_MISC | BPF_TAX, 0),
BPF_STMT(BPF_LD | BPF_LEN, 0),
BPF_STMT(BPF_ALU | BPF_ADD | BPF_X, 0),
BPF_STMT(BPF_MISC | BPF_TAX, 0), /* X == len - 3 */
BPF_STMT(BPF_LD | BPF_B | BPF_IND, 1),
BPF_STMT(BPF_RET | BPF_A, 0)
},
SKB,
{ 10, 20, 30, 40, 50 },
{ { 2, 10 }, { 3, 20 }, { 4, 30 } },
},
{
"tcpdump port 22",
.insns = {
{ 0x28, 0, 0, 0x0000000c },
{ 0x15, 0, 8, 0x000086dd },
{ 0x30, 0, 0, 0x00000014 },
{ 0x15, 2, 0, 0x00000084 },
{ 0x15, 1, 0, 0x00000006 },
{ 0x15, 0, 17, 0x00000011 },
{ 0x28, 0, 0, 0x00000036 },
{ 0x15, 14, 0, 0x00000016 },
{ 0x28, 0, 0, 0x00000038 },
{ 0x15, 12, 13, 0x00000016 },
{ 0x15, 0, 12, 0x00000800 },
{ 0x30, 0, 0, 0x00000017 },
{ 0x15, 2, 0, 0x00000084 },
{ 0x15, 1, 0, 0x00000006 },
{ 0x15, 0, 8, 0x00000011 },
{ 0x28, 0, 0, 0x00000014 },
{ 0x45, 6, 0, 0x00001fff },
{ 0xb1, 0, 0, 0x0000000e },
{ 0x48, 0, 0, 0x0000000e },
{ 0x15, 2, 0, 0x00000016 },
{ 0x48, 0, 0, 0x00000010 },
{ 0x15, 0, 1, 0x00000016 },
{ 0x06, 0, 0, 0x0000ffff },
{ 0x06, 0, 0, 0x00000000 },
},
SKB,
/* 3c:07:54:43:e5:76 > 10:bf:48:d6:43:d6, ethertype IPv4(0x0800)
* length 114: 10.1.1.149.49700 > 10.1.2.10.22: Flags [P.],
* seq 1305692979:1305693027, ack 3650467037, win 65535,
* options [nop,nop,TS val 2502645400 ecr 3971138], length 48
*/
{ 0x10, 0xbf, 0x48, 0xd6, 0x43, 0xd6,
0x3c, 0x07, 0x54, 0x43, 0xe5, 0x76,
0x08, 0x00,
0x45, 0x10, 0x00, 0x64, 0x75, 0xb5,
0x40, 0x00, 0x40, 0x06, 0xad, 0x2e, /* IP header */
0x0a, 0x01, 0x01, 0x95, /* ip src */
0x0a, 0x01, 0x02, 0x0a, /* ip dst */
0xc2, 0x24,
0x00, 0x16 /* dst port */ },
{ { 10, 0 }, { 30, 0 }, { 100, 65535 } },
},
{
"INT: DIV + ABS",
.insns_int = {
BPF_ALU64_REG(BPF_MOV, R6, R1),
BPF_LD_ABS(BPF_B, 3),
BPF_ALU64_IMM(BPF_MOV, R2, 2),
BPF_ALU32_REG(BPF_DIV, R0, R2),
BPF_ALU64_REG(BPF_MOV, R8, R0),
BPF_LD_ABS(BPF_B, 4),
BPF_ALU64_REG(BPF_ADD, R8, R0),
BPF_LD_IND(BPF_B, R8, -70),
BPF_EXIT_INSN(),
},
SKB_INT,
{ 10, 20, 30, 40, 50 },
{ { 4, 0 }, { 5, 10 } }
},
{
"check: missing ret",
.insns = {
BPF_STMT(BPF_LD | BPF_IMM, 1),
},
EXPECTED_FAIL,
{ },
{ }
},
};
static int get_length(struct sock_filter *fp)
{
int len = 0;
while (fp->code != 0 || fp->k != 0) {
fp++;
len++;
}
return len;
}
struct net_device dev;
struct sk_buff *populate_skb(char *buf, int size)
{
struct sk_buff *skb;
if (size >= MAX_DATA)
return NULL;
skb = alloc_skb(MAX_DATA, GFP_KERNEL);
if (!skb)
return NULL;
memcpy(__skb_put(skb, size), buf, size);
skb_reset_mac_header(skb);
skb->protocol = htons(ETH_P_IP);
skb->pkt_type = SKB_TYPE;
skb->mark = SKB_MARK;
skb->hash = SKB_HASH;
skb->queue_mapping = SKB_QUEUE_MAP;
skb->vlan_tci = SKB_VLAN_TCI;
skb->dev = &dev;
skb->dev->ifindex = SKB_DEV_IFINDEX;
skb->dev->type = SKB_DEV_TYPE;
skb_set_network_header(skb, min(size, ETH_HLEN));
return skb;
}
static int run_one(struct sk_filter *fp, struct bpf_test *t)
{
u64 start, finish, res, cnt = 100000;
int err_cnt = 0, err, i, j;
u32 ret = 0;
void *data;
for (i = 0; i < MAX_SUBTESTS; i++) {
if (t->test[i].data_size == 0 &&
t->test[i].result == 0)
break;
if (t->data_type == SKB ||
t->data_type == SKB_INT) {
data = populate_skb(t->data, t->test[i].data_size);
if (!data)
return -ENOMEM;
} else {
data = NULL;
}
start = ktime_to_us(ktime_get());
for (j = 0; j < cnt; j++)
ret = SK_RUN_FILTER(fp, data);
finish = ktime_to_us(ktime_get());
res = (finish - start) * 1000;
do_div(res, cnt);
err = ret != t->test[i].result;
if (!err)
pr_cont("%lld ", res);
if (t->data_type == SKB || t->data_type == SKB_INT)
kfree_skb(data);
if (err) {
pr_cont("ret %d != %d ", ret, t->test[i].result);
err_cnt++;
}
}
return err_cnt;
}
static __init int test_bpf(void)
{
struct sk_filter *fp, *fp_ext = NULL;
struct sock_fprog fprog;
int err, i, err_cnt = 0;
for (i = 0; i < ARRAY_SIZE(tests); i++) {
pr_info("#%d %s ", i, tests[i].descr);
fprog.filter = tests[i].insns;
fprog.len = get_length(fprog.filter);
if (tests[i].data_type == SKB_INT) {
fp_ext = kzalloc(4096, GFP_KERNEL);
if (!fp_ext)
return -ENOMEM;
fp = fp_ext;
memcpy(fp_ext->insns, tests[i].insns_int,
fprog.len * 8);
fp->len = fprog.len;
fp->bpf_func = sk_run_filter_int_skb;
} else {
err = sk_unattached_filter_create(&fp, &fprog);
if (tests[i].data_type == EXPECTED_FAIL) {
if (err == -EINVAL) {
pr_cont("PASS\n");
continue;
} else {
pr_cont("UNEXPECTED_PASS\n");
/* verifier didn't reject the test
* that's bad enough, just return
*/
return -EINVAL;
}
}
if (err) {
pr_cont("FAIL to attach err=%d len=%d\n",
err, fprog.len);
return err;
}
}
err = run_one(fp, &tests[i]);
if (tests[i].data_type != SKB_INT)
sk_unattached_filter_destroy(fp);
else
kfree(fp);
if (err) {
pr_cont("FAIL %d\n", err);
err_cnt++;
} else {
pr_cont("PASS\n");
}
}
if (err_cnt)
return -EINVAL;
else
return 0;
}
static int __init test_bpf_init(void)
{
return test_bpf();
}
static void __exit test_bpf_exit(void)
{
}
module_init(test_bpf_init);
module_exit(test_bpf_exit);
MODULE_LICENSE("GPL");

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@ -14,6 +14,12 @@ all: $(NET_PROGS)
run_tests: all
@/bin/sh ./run_netsocktests || echo "sockettests: [FAIL]"
@/bin/sh ./run_afpackettests || echo "afpackettests: [FAIL]"
@if /sbin/modprobe test_bpf ; then \
/sbin/rmmod test_bpf; \
echo "test_bpf: ok"; \
else \
echo "test_bpf: [FAIL]"; \
exit 1; \
fi
clean:
$(RM) $(NET_PROGS)